diff options
Diffstat (limited to 'libpthread/linuxthreads/spinlock.c')
-rw-r--r-- | libpthread/linuxthreads/spinlock.c | 12 |
1 files changed, 9 insertions, 3 deletions
diff --git a/libpthread/linuxthreads/spinlock.c b/libpthread/linuxthreads/spinlock.c index 80aeda529..ce970029e 100644 --- a/libpthread/linuxthreads/spinlock.c +++ b/libpthread/linuxthreads/spinlock.c @@ -188,10 +188,16 @@ int __pthread_unlock(struct _pthread_fastlock * lock) WRITE_MEMORY_BARRIER(); again: - while ((oldstatus = lock->__status) == 1) { - if (__compare_and_swap_with_release_semantics(&lock->__status, + oldstatus = lock->__status; + if (oldstatus == 0 || oldstatus == 1) { + /* No threads are waiting for this lock. Please note that we also + enter this case if the lock is not taken at all. If this wouldn't + be done here we would crash further down. */ + if (! __compare_and_swap_with_release_semantics(&lock->__status, oldstatus, 0)) - return 0; + goto again; + + return 0; } /* Find thread in waiting queue with maximal priority */ |